The problem of providing a tether post or stake to which an animal can be tied which is tangle-free has existed for literally hundreds of years. One of the earliest solutions to this problem is found in U.S. Pat. No. 223,872, issued in 1880. Other examples of attempts to solve this problem are found in U.S Pat. Nos. 227,675, 417,617, 444,661, 2,087,176 and 3,100,476. These devices have the common approach of providing a stake having an upper end which protrudes above ground level and an element which is pivotally or rotatably secured to the protruding end of the stake so that an animal tether can be tied to the rotatable element.
Unfortunately, however, prior animal tether post assemblies invariably have not been tangle-free in actual use. The animal will be tied to the stake by a flexible tether line, and as long as the animal keeps the line relatively taut, the rotatable portion of the tether stake will turn freely as the animal moves about the stake. These ideal conditions seldom, if ever, occur.
Typically, a tethered animal will wander around the tether stake in a random fashion with the tether line becoming slack and the animal passing close by the post or stake during its wanderings. This results in two problems which produce tangling of the tether line about the tether stake. First, the slack line will become looped or wrapped several times around the stake before the animal tries to pull the line taut. Secondly, any debris in the vicinity of the stake will be pulled by the tether line up next to the stake. This second phenomenon, when coupled with the likelihood of looping the slack line around the stake results in tangling of the tether line about the stake, very often with debris, to the point of greatly restricting the animal's mobility and freedom to move with respect to the stake.
Illustrative of the problems above described are U.S. Pat. Nos. 2,087,176 and 3,100,476. In both of these patents, the rotatable element to which the tether may be secured is located substantially at ground level. The flexible tether line, therefore, will drag debris to the stake or post. Additionally, the close proximity of the stake in U.S. Pat. No. 2,087,176 to the ground will virtually assure looping of the slack line over the stake top and any debris. In the device of U.S. Pat. No. 3,100,476, a pivotally mounted sleeve is provided to attempt to assist in unwinding of the tether rope from around the stake. The rotatable element and the sleeve, however, tend to move together as a unit, if they can rotate at all. Moreover, when animals of any size or strength are tethered to such a stake, the upward pull of the animal can bind the rotatable element and sleeve together to cause them to rotate as a unit and to inhibit rotation in general. Still further, the large eyelet portion of the rotatable element allows the tether line to move in close to the stake so that the moment arm which would enhance unraveling of the line from around the stake is reduced.
The net result of prior art tether stake assemblies has been that animals cannot be reliably tethered to the stake without tangling to the point of significantly reducing their mobility about the stake. Once the tether stake assembly becomes frozen so that it will not rotate, the animal invariably proceeds to wrap the line around the stake until he has progressively reduced the length of the tether to the point that it is dangerous to the unsupervised animal.